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I reorganized my seeds last week. Instead of having them in alphabetical order, I placed them in order of the dates when I wanted to take action on them.

So, some of them needed to be started last week. I used a baggie method and now have about 6 baby plants each of 3 types of cabbage, 2 types of broccoli, and 2 types of kohlrabi. I transplanted them to peat-pots today. Carrots and parsley have not yet sprouted.

I have only one light and it will only illuminate only one seed tray. I need to get these seedlings big and strong enough to go into the cold frame as quickly as possible. I still have room for the carrots and the parsley in the seed tray. However, the first of next month, I will have a whole new lot to germinate. And again, the same is true for March.

I expect I will need to invest in at least one more light fixture and seed tray. Furthermore, as the seedlings mature and outgrow their peat pot, I will transplant them and their peat pot into newspaper pots filled with Mel's Mix.

Does anyone know how I can determine when, and what, plants can go outside in the cold frame? I suspect weather is a variable, but are some plants more adaptable at an earlier date? Should the seedling be at some determined growth stage (2nd/3rd set of leaves, etc.) before going outside?

From my past experience, I am afraid I think you may have planted your seed about a month to 6 weeks too early for your zone, however I could be wrong... where did you get the recommended seed planting dates? The hours of daylight and the temperature may not be sufficient for your seedlings when they are mature enough to go out. Do you have a cold frame already built? Have you by any chance looked into doing a hot bed?

My information is from a seed starting Excel sheet - one where you supply your last average frost date. The plant names are in the program. Excel calculates the start date for germination.

I thought some of them sounded a bit early if one was considering a direct transplant to the garden. However, considering I was using a cold frame before the final planting, I thought I should be okay.

Yes, I have three large cold frames built and ready to use. I was planning on just setting them on the lawn and putting plants in pots in them.

I do not know enough about heating the cold frames. My first concern would be providing electricity. I have external outlets, but they are not conveniently located.

I am calculating May 5th this year as my last Frost Free Date and I'm in zone 5a. Its an unusually early date but I'm working with that one since I plan to use my coldframe, A-frame and also cover my early transplants. So even with my later Frost date than yours, you are starting earlier than my first indoor seed starting on Feb 11th for broccoli, cabbage, mache, and greens. I think Jan might be too early. My greens will go in the cold frame. The broc and cabb in the raised beds with extra heavy cover. I wanted an early start this year because I lost several brassicas to plus 90*F temps last spring and don't want that happening again.

Most greens like to be sown right outdoors a few weeks before last frost and not started indoors so they need to be transplanted, but you can always take the chance that you'll get good results. With using coldframes, you could start them 2-3 weeks ealier than the experts suggest right in the c'frames.

I hope your early start is beneficial to you. Let us know how it works out. We all learn from each other here.

I am growing celery for the first time this year and despite being in zone 5, I have started them indoorsThey are so slow to germinate and grow, they say to start them 12 weeks before last frost.The other one is asparagus, and last year I started my asparagus seeds in January.

I am still a bit confused. You suggested that by using cold frames, that I can start my plants 2-3 weeks earlier. Are you saying that I can sow them directly in the cold frame 2-3 weeks earlier? What about potted seedlings? Can they be placed outdoors in the cold frame 2-3 weeks earlier than they could transplanted outside?

What concerns me is that I will have too many seedlings indoors while having too little space and lights to accomodate them. I was hoping that the oldest seedlings may be able to free up some of that indoor space by moving to the outdoor cold frame. Since they will still be in pots, if the weather turns extremely cold, I can bring them indoors, or into the garage.

By starting these seeds early, I was hoping to save money on transplants, be able to grow types of plants that I am unable to find locally, and be able to get an early start on some veggies.

@camprn wrote:From my past experience, I am afraid I think you may have planted your seed about a month to 6 weeks too early for your zone, however I could be wrong... where did you get the recommended seed planting dates? The hours of daylight and the temperature may not be sufficient for your seedlings when they are mature enough to go out. Do you have a cold frame already built? Have you by any chance looked into doing a hot bed?

Is there a problem with starting things like tomatoes a couple of weeks early and just upgrading pots until you get them outside? I am planting some surprise tomato plants for a friend who lives in Spokane, there plant date is a full month after mine. But I thought if I got it ready it would have plenty of time to grow some tomatoes before her first frost.

Sorry to piggy back. I'm actually setting up my seed starting station right now and this comment caught my eye.

@camprn wrote:From my past experience, I am afraid I think you may have planted your seed about a month to 6 weeks too early for your zone, however I could be wrong... where did you get the recommended seed planting dates? The hours of daylight and the temperature may not be sufficient for your seedlings when they are mature enough to go out. Do you have a cold frame already built? Have you by any chance looked into doing a hot bed?

Is there a problem with starting things like tomatoes a couple of weeks early and just upgrading pots until you get them outside? I am planting some surprise tomato plants for a friend who lives in Spokane, there plant date is a full month after mine. But I thought if I got it ready it would have plenty of time to grow some tomatoes before her first frost.

Sorry to piggy back. I'm actually setting up my seed starting station right now and this comment caught my eye.

The biggest problem with planting too early, unless you have a greenhouse, is providing adequate heat and hours of light to maintain the plants and allow for proper growth. We can get a little bit of a head start on some of the common types of plants that we grow in our gardens, they really only need a head start by a month or six weeks. If the seed is sown too early the plants get leggy, are not sturdy, prone to things like fungus.... For me, sowing too early leads to frustration and few viable plants. This year I have chosen to expand my indoor growing station a little bit, so that I have fewer of these problems... Also, I am working on my patience. Yes I want to plant seeds now, but it is just too early, they would not survive. Check out Folia, it's a great site, with numerous tools I find valuable.

This site Folia offers tools to determine when to plant, days to transplant, dates to maturity etc. for specific vegetables. there is a lot of information here. For example, if I was planning on the calabrese broccoli and my last frost date is May 15, it suggests I sow seed April 3rd and set the plants in the garden on May first.

I have planted tomatoes and peppers too early for several years, just over anxious for spring.I likely will do it again. What I have found is that though I have coddled along seedlings in the greenhouse for months, the "volunteer tomato plants" quickly catch up and take over the plants that I had had growing for months.There comes a time when I just HAVE to see something grow.

Cold FramesFor an early start, sow seed in a cold frame and transplant it into the garden later (see Figure 1). Seed may be started as much as six weeks earlier than outdoors.

Here is the link: http://www.ext.colostate.edu/pubs/garden/07409.html

So, if I can sow seeds 6 weeks earlier by using a cold frame, does that also mean I can put seedling/transplants in the cold frame 6 weeks earlier? I think there was mention that the sun may not provide enough light. I am pondering all of this. I think I will give it a try and see what results I get. Worse case, I start new seeds and harvest the failed experiment.

Gwn, your comment, " the "volunteer tomato plants" quickly catch up and take over the plants that I had had growing for months." is very interesting. Perhaps for some plants we should practice wintersowing. Just as nature seeds our garden and surprises us with the volunteers, we could intentionally plant seeds outside and wait for them to germinate when the time is right. I think in my zone, I will still need to get an early start on tomatoes and peppers. Otherwise, I would never get a harvest. However, some plants - I hear - do well by self-seeding for the following year. I had plenty of marigolds last summer that just showed up!

MijejoI recall February is the time for starting tomato seeds here, then March/broccoli for later transplanting into the ground. I'm only an hour and 1/2 from you, hmm. Maybe you can ask a nursery manager in your area. I wish I could help more but I've never used cold frames.

It you start your cool weather seeds too early in the cold frame you won't be out but a few seeds so to me its always worth a try.

Yes, you can also put potted seedlings in your coldframe but be sure they're covered so they get all the advantages of the sun and heat and none of the frost and cold. They'll slow down to a crawl in growth if its too cool but will catch up when the heat arrives.

I transplanted a couple of Matt's Wild Cherry toms right in my A-frame and got fruits in July which is early for me. They are on both left and right sides in the middle so they can grow upwards along the tallest section. I also had carrots, mesclun mix, spinach and my young lettuce starts along with a tray of newly-seeded lettuce in the A-frame.

Don't be hesitant. Just try it to see if it works. You're in a warmer zone than me.

Bumping this thread because it is still of great interest to me. I hope others will benefit from it as well. Last year, I did use the cold frames to get an early start and I had great success with them.

Both last year, and again this year, I start many of my plants from seed inside. I start first with the cold hardy crops. When they are up-potted, I started seeds for the warmer crops.

At this time, I have already up-potted once (sometimes twice) the cold hardy crops. They are taking up too much room indoors and I think I will move them to the cold frames. We are expecting some warm weather for a few days. I think this will give them a good start. If the weather turns too cold, I will have to take some action to keep them warm (move inside, cover with blannkets, add electric/solar heat, etc.)

Once they leave my indoor growing area, I will up-pot the warmer crops. They will continue to stay inside for a few more weeks. When I remove the cold hardy crops from the cold frame and transplant them into the garden, I will move the warmer crops to the cold frame.

It is all aboout staging. This is my 3rd year SFGing (or any gardening), and second using the cold frames. I still have a lot to learn, but I am enjoying the experimentation, as well as the harvests!

In summary, I think the cold frames allow me to start indoors each type of seedling up to a month earlier (with varying successes). Fine tuning those dates for each type of crop and maybe each variety will come with more experience. The cold frames do not let me get the plants planted in the garden any sooner, but gives me a head start on their size. In addition, having the started plants makes planning the garden (such as what goes where) easier because I can anticipate each type of crop and how many I expect to have. Alas, i will probably always over plant, but those extras are graciously accepted by neighbors, friends, and relatives.

We built a cold frame last fall and I put spinach plants from the summer in. (they had all been eaten by the deer but the base part of the plant was intact. We had TONS of snow this year and I did not clear the snow off the frame for fear of breaking the glass. When I finally did,(early February) the spinach was doing very well. We have had 2 meals in Feb with the spinach and last night had a VERY large feed. The leaves now are extremely health and 4 inches long.I am curious at what date (in relation to last frost) would you leave the lid off the cold frame?The reason I ask is that I am thinking of possibly growing tomatoes in the cold frame and then just leaving off the lids when the time comes

I would think that leaving the lid off would not be much different than planting directly outside. The difference might be that the soil, roots and lower part of the stem would not be subject to the wind. If I were trying that method, I would leave the lid off on warm days, cover it again at night, and then wait until my last frost date (not AVERAGE last frost date) which is mid May for me, before I took the lid completely off. However, since in my season, I am still growing and harvesting tomatoes until late September, or early October, I would not choose this method, because it would tie up my cold frame when I would want to start cold crops or crops to over winter (like the spinach you mentioned). Keep us informed with what you do and how it works out for you. Thanks.

For this year, I plan to grow a Tiny Tim tomato in my cold frame. Remember, a determinate gives you a flush harvest for about 3 weeks and then nothing more so you can pull the plant and have room for your fall crops.

I've built a regular cold frame to go along with my A-frame to extend my season. I found that the cold frame itself was a great way to harden off any new seedlings going outdoors. They could be easily covered for the night or shaded during the day before they got acclimated to the bright sun.I could grow lettuces and spinach in the coldframe pretty much all summer long with the help of cheesecloth draped across the top to shade them.lettuces under shade cloth in cold frame.

This post has been very informative to me. I also am in the northern Cincinnati area and am just itching to get started on my SFG. This is my first year of any type of gardening and I already planted spinach and lettuce seedlings. I was wondering some of the things you addressed in your experience last year. I don't have any cold frames built yet, but had planned on doing so. If I understand this correctly, you are waiting until the seedlings get large enough to put in pots and then you are putting the pots outside in the cold frames? Right now my seedlings are in those little Jiffy Peat pods under lights and when they get a little bigger I'll transplant them into larger pots. Do you recommend a size for the pots that are going into the cold frame?

I know my question probably sounds stupid but I'm starting to get a little overwhelmed with what I have planted to far and figuring out the next step for them.

Where are you located in the Cincinnati area? I am in West Chester near the Sharonville border.

I also use the Jiffy peat pots and I am experimenting with the soil blocks, as well. Last year, when I up-potted, I used various sized pots. It just depended on the plant, how big it was at the time, and how large I anticipated it becoming before it was transplanted to a spot in the garden. For example, if a Jiffy pot was over seeded and numerous seedlings existed that I thought I could save, and the seedlings were small, I used small pots to up-pot them, say maybe 3" for things like various herbs that would grow slow and stay small. Tomatoes would be up-potted more than once, and each time they would be deeply potted so that very little of their stems were above the soil (remove those lower leaves first) and only a few leaves were sticking out the soil. If you are new to gardening you may not know that tomatoes (and others in their family) can grow roots from those tiny "hairs" on their stems. Giving the plants a start with a good root mass is a bonus - so bury those stems while the plant is small. My tomato plants are still inside under lights and will be one of the last plants to go to the cold frame and ultimately into the garden. They have been up-potted once or twice already and are in need of another within the week. Most of them are now in red Solo cups and will graduate to the next sized cup.

I am both frugal and environmentally conscious, so for pots, I reuse what I already have or what is becoming disposed. Last year, I remember plants in the cold frame being in containers such as 1/2 gallon milk/juice containers, pots made from newspaper foldings, old pots - maybe 4" from nursery plants and any other container I could find in which I could put a few drainage holes. I also grew things like a salad blend in which I did not isolate the individual plants. They grew well in the cold frame in food take-out containers. Some of these were seeded indoors and some were seeded in the cold frames. Both worked out well. You can overseed them and eat what you thin out. Nibble-away-while-you-work are the perks of this type of gardening!

There are important things to remember about using cold frames. You have to be devoted to ensuring they are vented on sunny/warm days. Think of how warm a car gets with windows shut. Those frames heat up fast! I am more concerned with them over heating than I am with them getting too cold. Another thing I experienced are slugs and aphids. I suppose since predatory methods (birds and other insects) do not visit inside the cold frames, populations of these pests can boom. I had slug infestations last spring and aphids in the fall. That was my experience last year - and my only year using the cold frames - well until the start of this year. So, be on the look out for these and get them under control ASAP. Also, do not let the plants become root-bound. That is when the roots are crowded and start growing around in a circle in the pot. You need to up-pot to prevent this. Plants in small containers frequently use up all of the nutrients in those pots, so up-potting with new soil/MM will keep them thriving. I do not use fertilizer.

I hope this helps! I love the cold frames. My indoor seedlings quickly over take the area indoors and the cold frames let me get them out of there so there is room for the younger smaller ones to be up-potted. In addition, because of the cold frames, we were eating huge salads of leafy lettuces and greens very early last year and into late fall.